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1.
Mixed convection peristaltic flow of Jeffrey nanofluid in a channel with compliant walls is addressed here. The present investigation includes the viscous dissipation, thermal radiation and Joule heating. Whole analysis is performed for velocity, thermal and concentration slip conditions. Related problems through long wavelength and low Reynolds number are examined for stream function, temperature and concentration. Impacts of thermal radiation, Hartman number, Brownian motion parameter, thermophoresis, Joule heating and slip parameters are explored in detail. Clearly temperature is a decreasing function of Hartman number and radiation parameter.  相似文献   
2.
An acid phosphatase from crude culture filtrate of Aspergillus ficuum was purified to homogeneity using three ion exchange chromatographic steps. SDS-PAGE of the purified enzyme gave a single stained band at approximately 68-KDa. The mobility of the native enzyme in gel filtration chromatography, however, indicated that the molecular mass to be about 130-KDa implying the active form to be a dimer. On the basis of a molecular mass of 68-KDa, the molar extinction coefficient of the enzyme at 280 nm was estimated to be 3.4 x 10(5) M-1 cm-1. The isoelectric point of the enzyme, as judged by chromatofocusing, was about 4.0. The purified enzyme is highly stable at 0 degree C. Thermal inactivation studies have indicated that the enzyme is unstable at 70 degrees C. The enzyme, however, exhibited a broad temperature optima with a maximum catalytic activity at 63 degrees C. The Km of the enzyme for p-nitrophenylphosphate is about 270 microM with an estimated turnover number of 2550 per sec. The enzyme is a glycoprotein as evidenced by the positive PAS staining; the sugar composition suggests the presence of N-linked high mannose-oligosaccharides. A partial N-terminal amino acid sequence up to the twenty-third residue was obtained. The enzyme was inhibited competitively by inorganic orthophosphate (Ki = 185 microM) and non-competitively by phosphomycin (Ki = 600 microM).  相似文献   
3.
Purified Aspergillus ficuum phytase's partial primary structure and amino acid and sugar composition were elucidated. Determination of kinetic parameters of the enzyme at different pH values and temperatures indicated no significant alteration of the Km for phytate while the Kcat was affected. The enzyme was able to release more than 51% of the total available Pi from phytate in a 3.0 hr assay at 58 degrees C, but the Kcat dropped to 15% of the initial rate. Substrate selectivity studies revealed phytate to be the preferred substrate. The pH optima of phytase was 5.0, 4.0, and 3.0 for phytate, ATP, and polyphosphate, respectively. The enzyme had varied sensitivity towards cations. While Ca++ and Fe++ produced no effect on the catalytic rate of the enzyme, Cu+, Cu++, Zn++, and Fe were found to be inhibitory. Mn++ was observed to enhance enzyme activity by 33% at 50 microM. Known inhibitors of acid phosphatases e.g. L (+)-tartrate, phosphomycin, and sodium fluoride had no effect on enzyme activity.  相似文献   
4.
The structure of the hernoglobin α-chain of Rose-ringed Parakeet was determined by sequence degradations of the intact subunit, the CNBr fragments, and peptides obtained by digestion with staphylococcal Glu-specific protease and trypsin. Using this analysis, the complete α-chain structure of 21 avian species is known, permitting comparisons of the protein structure and of avian relationships. The structure exhibits differences from previously established avian α-chains at a total of 61 positions, five of which have residues unique to those of the parakeet (Ser-12, Gly-65, Ser-67, Ala-121, and Leu-134). The analysis defines hemoglobin variation within an additional avian order (Psittaciformes), demonstrates distant patterns for evaluation of relationships within other avian orders, and lends support to taxonomic conclusions from molecular data.  相似文献   
5.
Improper timing of artificial insemination with respect to ovulation is one of the major factors hampering the conception rate in buffalo. The present study was an attempt to relate physio-chemical changes in estrual mucus to subsequent pregnancy status in order to find their optimal values for determining the time for artificial insemination (AI). Serum estradiol, total protein and dry matter contents of estrual mucus were evaluated to predict the subsequent pregnancy in 36 buffalo during October 1988 to February 1989. Serum estradiol was determined by radioimmunoassay (RIA); spinnbarkeit, dry matter and total protein were determined by standard methods. Multivariate probit analyses were carried out to relate these variables to subsequent pregnancy status. Elasticity and protein concentration were significantly related to prediction probability of pregnancy status, and they predicted the pregnancy status 86% of the times correctly (P < 0.05). The probability of pregnant animals being correctly classified was 0.76, whereas the corresponding value for non-pregnant animals was 0.95. The present study demonstrated the possibility of using such a statistical model on mucus characteristics for determining proper AI time for better conception rates in Nili-Ravi water buffalo.  相似文献   
6.
Summary As the initial step in a project to provide a more cost-effective source of the phytase enzyme, this paper reports on the use of a polyclonal antibody raised to phytase purified from an isolate of Aspergillus niger (A. ficuum) to screen an A. niger lambda gt11 expression library and the use of amino acid sequencing to identify a clone containing part of the fungal phytase gene. The described use of amino acid sequence fragments to verify the cloning of a gene has potential applications in other cloning projects.Mention of a trademark or proprietary product does not constitute a guarantee or warranty by the U.S. Department of Agriculture and does not imply approval to the exclusion of other products that may also be suitable Offprint requests to: E. Mullaney  相似文献   
7.
Sequence analysis of the simian foamy virus type 1 genome.   总被引:11,自引:0,他引:11  
J J Kupiec  A Kay  M Hayat  R Ravier  J Périès  F Galibert 《Gene》1991,101(2):185-194
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8.
M. Hayat 《BioControl》1972,17(1):99-106
An account of the Indian species of the genusEretmocerus Haldeman is given. Three new species (E. indicus sp. n.,E. mashhoodi sp. n.,E. gunturiensis sp. n.) are described. Three species (E. haldemani Howard,E. mundus Mercet,E. corni Haldeman) are reported for the first time from India. A revised key to the known species of the genus is also given.
Résumé Une révision des espèces indiennes du genreEretmocerus Haldeman est donnée. Trois nouvelles espèces (E. indicus, E. mashhoodi, E. gunturiensis) sont décrites, trois autres espèces (E. haldemani Howard,E. mundus Mercet,E. corni Haldeman) sont signalées pour la première fois de l’Inde. Une clé révisée des espèces connues de ce genre est proposée.
  相似文献   
9.
Allogeneic bone marrow grafts carried out after previous administration of antilymphocytic serum alone were attempted in 16 patients. Of these, six had acute myeloblastic leukaemia, four acute lymphoblastic leukaemia, and one a blast cell crisis in polycythaemia vera. Ten of these patients were in an overt phase of the disease and resistant to chemotherapy, while nine had complete agranulocytosis. In five of these patients erythrocyte and leucocyte antigenic markers demonstrated the establishment of the graft. One patient had thalassaemia major, and four others had aplasia of the bone marrow, in one case due to chloramphenicol poisoning and in another to virus hepatitis. The grafts were successful in the last two patients and transformed their clinical condition.No signs of early acute secondary disease were noted in any of the patients, either when the donor had been given antilymphocytic serum or when he was untreated. The grafts had no adoptive immunotherapeutic effect on the acute leukaemia. These observations have clearly shown that antilymphocytic serum has an immunosuppressive effect in man when it is used alone.  相似文献   
10.
Simple acidification of aqueous alkaline peroxynitrite quantitatively generates singlet (1Δg) molecular oxygen, detected and quantitated spectroscopically (1270 nm). This observation provides a chemical basis for physiological cytotoxicity of ONOO? generated in the diffusion - controlled reaction of cellular NO? and O. The experiments consist of (i) chemical generation of ONOO? from NO? gas and KO2 powder in alkaline aqueous solution; (ii) absorption spectral identification of ONOO? in the near-UV with maximum at 302 nm; (iii) spectroscopic identification of 1O2 by its emission band at 1200–1340 nm with maximum at 1275 nm; and (iv) quantitation of 1O2 generated in ONOO?/H+ reaction by comparison of the chemiluminescence intensity at 1270 nm with that from H2O2/OCl? reaction that generates 1O2 with unit efficiency at alkaline pH. 1O2 was generated with unit efficiency with respect to ONOO? concentration by the ONOO?/H+ reaction.  相似文献   
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